Looking to see what others are running for spark plugs on there Robins. I downloaded the owners manual and it said nothing about what spark plug should be in there. I slapped a NGK BH7 in there and runs good. However it is about a 1/4 - 1/2 inch shorter than the old Bosch I pulled out of there..
What are you guys running and does plug depth (how far it reaches into the cylinder) affect performance ??